Luminous means having LEDs arranged on fold-out surfaces

Abstract

A luminous means is disclosed, the luminous means having LEDs on a substrate, an outer bulb in which the substrate having the LEDs is arranged, and a cap, wherein at least two partial surfaces of the substrate are folded out with respect to the remaining substrate around a bridge area in each case, via which the particular partial surface is connected to the remaining substrate, and are thus set obliquely with respect to the remaining substrate which is flat per se, wherein, for each side surface of the remaining substrate, which side surfaces are opposite one another with respect to a thickness direction of the remaining substrate, at least one partial surface is folded out in each case, and wherein at least one of the LEDs is arranged on each of the partial surfaces.

The invention claimed is: 
     
       1. A luminous means comprising:
 a plurality of LEDs for emitting light; 
 a substrate; 
 a conductive track structure on the substrate, on which substrate the LEDs are mounted and thereby electrically conductively connected with the conductive track structure; 
 an outer bulb which is transmissive for the light emitted by the LEDs, in which the substrate having the LEDs is arranged; and 
 an electrically conductive lamp base with which the LEDs are electrically operably connected via the conductive track structure, wherein the electrically conductive lamp base is configured to be received by a power socket external to the luminous means; 
 wherein at least two part surfaces of the substrate are each folded out relative to a remainder of the substrate about a respective bridge region via which the respective part surface is connected to the remainder of the substrate, folded-out and thus inclined relative to the remainder of the substrate, which is flat; 
 wherein, for each side surface of the remainder of the substrate, which side surfaces are mutually opposite in relation to a thickness direction of the remainder of the substrate, in each case at least one part surface is folded out; and 
 wherein at least one of the LEDs is arranged on each of the part surfaces. 
 
     
     
       2. The luminous means according to  claim 1 , in which, for each side surface of the remainder of the substrate, at least two part surfaces are folded out, on each of which at least one of the LEDs is mounted, wherein the part surfaces are each folded out by at least 25° and at most 65° relative to the remainder of the substrate. 
     
     
       3. The luminous means according to  claim 1 , in which, for each side surface of the remainder of the substrate, at least two part surfaces are folded out, on each of which at least one of the LEDs is mounted, wherein the part surfaces are each folded out by at least 70° and at most 110° relative to the remainder of the substrate. 
     
     
       4. The luminous means according to  claim 2 , in which, for each side surface of the remainder of the substrate, at least four part surfaces are folded out, which at least four part surfaces for each side surface of the remainder of the substrate are radially symmetrical with one another about a common axis of rotation. 
     
     
       5. The luminous means according to  claim 1 , in which the substrate is composed of at least two substrate layers which are each flat and are assembled to form a multilayer substrate, wherein the part surfaces are each a part region of one of the substrate layers, which part regions are folded out relative to the respective remainder of the substrate layer about the bridge region, wherein at least one part region is folded out from each substrate layer. 
     
     
       6. The luminous means according to  claim 5 , in which the substrate has a joint connecting layer with which the substrate layers are connected together by a material-based connection. 
     
     
       7. The luminous means according to  claim 5 , in which, for each substrate layer, the at least one part region is in each case folded out to an outer side surface of the respective substrate layer, which outer side surfaces are each at the same time a side surface of the substrate. 
     
     
       8. The luminous means according to  claim 5 , in which, for each substrate layer, the at least one part region is partially separated from the remainder of the substrate layer by a respective parting line which passes through the respective substrate layer in the thickness direction thereof and extends wholly within the respective substrate layer in relation to the surface directions thereof. 
     
     
       9. The luminous means according to  claim 5 , in which the substrate has a carrier which is arranged at least in some regions between the substrate layers, wherein the carrier has a higher bending stiffness than the substrate layers in each case separately. 
     
     
       10. The luminous means according to  claim 5 , in which the substrate has a flat reflector which is arranged between the substrate layers, wherein the LEDs arranged on the folded-out part regions are each arranged on an inner side surface of the respective substrate layer facing the reflector, so that, for each LED, at least a part of the light is incident on the reflector. 
     
     
       11. The luminous means according to  claim 10 , in which the substrate has a carrier which is arranged at least in some regions between the substrate layers, wherein the carrier has a higher bending stiffness than the substrate layers in each case separately, and in which the carrier is at the same time the reflector. 
     
     
       12. The luminous means according to  claim 5 , in which the LEDs are each mounted on an outer side surface of the respective substrate layer, which outer side surfaces are each at the same time a side surface of the substrate. 
     
     
       13. The luminous means according to  claim 5 , in which the substrate layers each have a thickness of at least 150 μm and at most 500 μm, and respective conductive tracks are provided on each of the substrate layers as part of the conductive track structure, which conductive tracks each have a thickness of at least 20 μm and at most 100 μm. 
     
     
       14. The luminous means according to  claim 1 , in which a light distribution generated with the luminous means is homogenized in that light intensity values taken on a circular path around an outer bulb longitudinal axis at an angle of 90° to an outer bulb longitudinal direction in each case represent at least 30% of a maximum value of the light intensity taken on the circular path. 
     
     
       15. The luminous means according to  claim 1 , having a heat sink which is provided in direct thermal contact with the substrate and forms an outer surface of the luminous means or is provided in direct thermal contact with a part forming an outer surface of the luminous means, wherein the heat sink has a thermal resistance (R th ) of at most 25 K/W. 
     
     
       16. The luminous means according to  claim 15 , in which the heat sink is assembled from at least two parts, which heat sink parts together enclose the substrate. 
     
     
       17. The luminous means according to  claim 1 , in which the outer bulb is made from glass and delimits a closed volume filled with a filling gas, which filling gas has a higher thermal conductivity than air. 
     
     
       18. The luminous means according to  claim 17 , in which the substrate having the conductive track structure is arranged wholly within the filling gas volume and is preferably free from driver electronics. 
     
     
       19. A method for producing a luminous means according to  claim 1 , the method comprising:
 providing the substrate; and 
 folding out the part surfaces from the remainder of the substrate. 
 
     
     
       20. A method for producing a luminous means according to  claim 8 , wherein the parting lines are introduced by means of at least one of a mechanical cutting tool, a stamping tool, and laser cutting. 
     
     
       21. The method according to  claim 19 , in which the conductive track structure is locally plastically deformed when the part regions are folded out. 
     
     
       22. A method for producing a luminous means according to  claim 5 , wherein the part regions are already each folded out of the remainder of the substrate layer when the substrate layers are assembled.